Footwear for sports such as skiing, snowboarding, mountaineering, or skating, is sport specific. Typically footwear for these sports is heavy, bulky, rigid and difficult to walk in, and only suitable for use in specific sporting applications.
For example, ski and mountaineering boots are typically made of stiff plastic to support the ankle and lower leg. Ski boots are designed for high lateral stiffness for precision and responsiveness when skiing, and mountaineering boots are stiff to facilitate crampon attachment and use. However, such stiff boots are difficult to walk in, heavy, and bulky, so mountaineers typically carry separate approach boots or shoes.
Snowboarding bindings typically use a support that encloses a boot with a soft upper. The support has a stiff base-plate which continues up the back of the ankle and lower leg to rigidly support the soft boot. Snowboarding boots may be stiff or flexible and are bulky so do not facilitate walking more than a short distance, or walking over steep or uneven terrain. Snow board boots and bindings are also heavy and bulky.
Ski-mountaineering and back-country or cross-country skiing combine the sport of skiing with hiking, trekking or mountaineering. In these pursuits, the skier needs to walk or climb to gain altitude without the assistance of chair lifts or tow ropes, and some travel, especially in an approach to a climb, may be over terrain that is not snow covered.
When a back-country skier or mountaineer reaches terrain that can't be traversed on skis, they must remove their skis and traverse that terrain by foot. If the terrain is covered by hard snow or ice, the skier will swap their skis for crampons. This typically involves removing their backpack, and sitting down to attach the crampons to their boots. If the slope is steep and icy, it may be difficult to find a safe place to do this, and a backpack resting on a sloped surface of hard snow or ice is at risk of sliding down the slope. Additionally, when the skier first steps out of their skis, the skier is at risk of slipping until they have fitted crampons.
By nature, ski-mountaineering and back-country skiing trips typically take place in remote, unpatrolled areas and may be multi-day trips, requiring the skier to carry camping gear in addition to equipment such as avalanche rescue gear and survival gear. Therefore, light weight compact gear is highly desirable in these pursuits.
Existing exoskeletons for attaching boots or other footwear to sporting equipment typically have rigid bases so are not suitable for walking. U.S. Pat. No. 6,691,434 describes an exoskeleton design having a rigid base. The rigidity of that system also relies on bracing extending up the back of the leg which makes the system bulky and heavy. Additionally, the system is designed to provide lateral tilting movement/tilting of the boot, which is undesirable for good ski control.
U.S. Pat. No. 5,815,953 and U.S. Pat. No. 4,955,149 also describe brace systems for attaching a walking boot to skis. Both of these systems have rigid soles with a hinge behind the heel to allow some ankle movement. Transverse, flexible straps secure the boot in place but provide little or no lateral stiffness. US 2008/047168 describes a brace that allows some flexure of the foot through the use of an underfoot hinge. This system is permanently secured to the item of sporting equipment and has no straps to retain a boot or shoe in place or to prevent movement of the footwear relative to the brace. This brace provides very little lateral support for the foot.
U.S. Pat. No. 5,823,563 describes a method of attaching ‘crampons’ to the front part of a ski boot and mounting the boot and crampon arrangement to skis. This system requires ski boots and is not suitable for use with standard walking boots. Additionally the ‘crampons’ in this system are only under the front part of the boot, and only have underfoot points with no heel or front points. Therefore, they would be of little practical use on hard snow or ice.
There is a need for an exoskeleton for attaching standard walking or hiking boots or shoes to sports equipment in a way that provides the necessary rigidity to the foot for the sporting pursuit, so a user can wear the same footwear for walking and with the sports equipment. It is desirable for such an attachment to be lightweight and easily dismantled or collapsed for storage or transport.
In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents or such sources of information is not to be construed as an admission that such documents or such sources of information, in any jurisdiction, are prior art or form part of the common general knowledge in the art.
It is an object of at least preferred embodiments of the present invention to provide an improved apparatus for attaching an item of footwear to sports equipment, or to at least provide the public with a useful choice.